The present invention relates to an electromagnetic relay of a flat configuration which can switch electric contacts by producing a seesaw movement of an armature.
An electromagnetic relay of the type described is disclosed in, for example, U.S. Pat. No. 4,912,438 assigned to the same assignee as the present invention. The relay described in this U.S. patent has a movable armature assembly having movable contacts, a coil assembly implemented as a coil spool having a core and wound with a coil, and an insulating base supporting stationary contacts, coil terminals, and connection terminals. Such a conventional relay has a drawback that the space or insulation distance available between the joints of coil terminals and the contacts and the space or insulation distance available between the coil and the contacts are limited, whereby the withstanding voltage available between the coil and the contacts is limited. Generally, the contact force of contacts, which is one of major factors that determine the characteristics of an electromagnetic relay, is dependent on the distance between the ends of the core and the stationary contacts. Therefore, another problem with the above-stated prior art relay is that the combination of the coil assembly and the base which are physically independent of each other and include the core and the stationary contacts, respectively, effects the distance between the ends of the core and the stationary contacts, rendering the contact force unstable. Moreover, after the assembly of the relay, the above-mentioned distance changes with the changes in temperature and other environmental conditions to thereby influence the characteristics of the relay.